(1) Field of the Invention
The present invention relates to the art of a connection setting method for use in a network, which is suitable for when a connection is made between communication terminals in a network defined by interconnection among a plurality of switches accommodating the communication terminals.
To put it concretely, this invention relates to the art of a network connection setting method suitable for when, while consideration is given to a quality of service (QoS) as to cell loss, cell transmission delay and others, a connection is established between the communication terminals in a network, for example, employing the asynchronous transfer mode (ATM) on broadband aspects of ISDN (B-ISDN).
(2) Description of the Related Art
In recent years, for the purpose of transferring multimedia information comprising a plurality of types of information such as voices, data and pictures at a high speed through the use of one network, research and development have noticeably advanced for an ATM network, employing asynchronous transfer mode (ATM).
This ATM network is established with the interconnection among a plurality of switches allowed to accommodate communication terminals, and although being already placed into practical use, there is a further need to establish a method of efficiently making the most of network resources or a method of making a connection meeting a requirement efficiently at a high speed for the improvement of a quality of service, (QoS requirement).
Meanwhile, the TINA (Telecommunication Information Networking Architecture) has been proposed as a network architecture leading the following generation.
The TINA is made in such a manner that, through a control network to a communication network created by interconnecting a plurality of switches accommodating communication terminals, there are connected a control system functioning as an EML-CP (Element Management Layer-Connection Perform) for monitoring and controlling each of the plurality of switches and a control system functioning as an NML-CP (Network Management Layer-Connection Perform) for monitoring and controlling the whole network.
The functions of the NML-CP and EML-CP can be distributed to a plurality of control systems through the use of, for example, a distributively computing technique represented by the CORBA (Common Object Request Broker Architecture and specification) or the like.
In this TINA, the employment of the ATM network as the communication network has been in examination.
There is a problem which arises with the TINA, however, in that there is no establishment of a method of efficiently making the most of network resources or a method of making a connection meeting the QoS requirement efficiently at a high speed, for that the relationship between the NML-CP and the EML-CP and the functional distribution therebetween still remain undefined clearly.
The present invention has been developed with a view to eliminating this problem, and it is therefore an object of this invention to provide a connection setting method for use in a network, a network monitoring control system and an element monitoring control system, coupled with a computer-readable record medium retaining a network monitoring control program and a computer-readable record medium retaining an element monitoring control program, which are capable of making clear the relationship between an NML-CP and an EML-CP and the functional distribution therebetween to set a connection meeting the QoS requirement efficiently at a high speed while making the most of network resources efficiently.
For this purpose, in accordance with this invention, there is provided a network connection setting method in which, in a network produced by interconnection among a plurality of element units accommodating communication terminals, for making a connection between the communication terminals, a network monitoring control system, for monitoring and controlling the whole network, selects the element units constituting a path for setting up the connection, on the basis of a connection setting request information, including quality information about the connection to be set up and outputted from the communication terminal requesting the connection, and an element monitoring control system, for monitoring and controlling one of the selected element units, under control of the network monitoring control system as its object, secures a resource for making said connection in cooperation with an element monitoring control system for monitoring and controlling another one of the selected element units, which is a part of the path and is adjacent to said object element unit, and controls the object element unit through the resource for setting up the connection, and the network monitoring control system evaluates the result of connection setting control by the element monitoring control systems to judge whether or not it meets the quality information as a whole.
To put it concretely, in accordance with this invention, there is provided a network connection setting method in which, in a network produced by interconnection among a plurality of element units accommodating communication terminals, for making a connection between the communication terminals, the communication terminal requesting a connection outputs, to a network monitoring control system for monitoring and controlling the whole network, connection setting request information, including identification information on the connection-requesting side communication terminal and the connection-accepting side communication terminal and quality information on the connection to be set up, the network monitoring control system receives the connection setting request information and selects the element units constituting a path for setting up the connection on the basis of the identification information on the connection-requesting side and connection-accepting side communication terminals, included in the connection setting request information and, further, outputs, to an element monitoring control system for monitoring and controlling one of the selected element units as its object, in-element-unit connection setting request information, including identification information on another element unit adjacent to the object element unit and quality information on the connection to be set up, and the element monitoring control system, for monitoring and controlling the object element units, receives the in-element-unit connection setting request information from the network monitoring control system, secures a resource for setting up the connection meeting the quality information in cooperation with an element monitoring control system for monitoring and controlling the element unit adjacent to the object element unit, and controls the element unit for setting up the connection through the secured resource, and the network monitoring control system receives the result of connection setting control by the element monitoring control units and evaluates the result of connection setting control to judge whether or not it meets the quality information as a whole.
At this time, if judgment is made that the result of connection setting control by the element monitoring control systems does not wholly meet the aforesaid quality information, the network monitoring control unit can also reselect element units constituting the aforesaid path.
In addition, in accordance with this invention, there is provided a network monitoring control system for monitoring and controlling the whole network formed by interconnection among a plurality of element units accommodating communication terminals, comprising a connection setting request information receiving section for receiving connection setting request information, including identification information on the connection-requesting side communication terminal and the connection-accepting side communication terminal and quality information on the connection to be set up from the connection-requesting side communication terminal, a selecting section for selecting the element units constituting a path for setting up the connection on the basis of the identification information on the connection-requesting side communication terminal and the connection-accepting side communication terminal included in the connection setting request information received by the connection setting request information receiving section, a request information outputting section for outputting, to an element monitoring control system for monitoring and controlling one of the element units selected by the selecting section as its object, in-element-unit connection setting request information, including identification information on another one of the selected element units adjacent to the object element unit and further including the quality information on the connection to be set up, and an quality evaluating section for receiving a connection setting control result from the element monitoring control systems receiving the in-element-unit connection setting request information from the request information outputting section, to make judgment on whether or not the connection setting control result meets the quality information included in the connection setting request information as a whole.
In this case, the selecting section comprises a physical connection information retaining table for retaining information on a physical connection relationship between the plurality of element units in the network, and a determining section for referring to the physical connection information retaining table on the basis of the identification information on the connection-requesting side and connection-accepting side communication terminals included in the connection setting request information for determining the element units to be selected, constituting the path for setting the connection.
At this time, the determining section can also determine the element units to be selected taking into consideration the condition for determining the path.
In addition, in the case that the quality evaluating section makes judgment that the connection setting control result does not meet the quality information as a whole, the selecting section can also reselect element units constituting the path.
Moreover, in accordance with this invention, there is provided an element monitoring control system for, in a network formed by interconnection among a plurality of element units accommodating communication terminals, monitoring and controlling at least one of the plurality of element units as its object, comprising a request information receiving section for, if the object element unit is selected as an element unit constituting a path for making a connection between the communication terminals, receiving, from a host system, an in-element-unit connection setting request information, including identification information on another element unit constituting the path and adjacent to the object element unit and further including quality information on the connection to be set up, a resource securing section for securing a resource needed for setting up the connection meeting the quality information on the basis of the request information received by the request information receiving section in cooperation with an element monitoring control system for monitoring and controlling the adjacent element unit, a connection setting control section for controlling the object element unit to set up the connection through the use of the resource secured by the resource securing section, and an informing section for informing the host system of the result of connection setting control by the connection setting control section.
In this case, the resource securing section is made up of an adjacent element unit connection information retaining table for retaining identification information on another element unit adjacent to the object element unit, identification information on the element monitoring control system for controlling the adjacent element unit and identification information on a connecting place for making a physical connection between the object element unit and the adjacent element unit, a state managing section for grasping and managing a state of the object element unit, a resource candidate determining section for referring to the adjacent element unit connection information retaining table and the result of management by the state managing section, on the basis of the request information received by the request information receiving section, to determine a candidate for a resource for setting up the connection corresponding to the quality information, and a cooperation-with-adjacent-element-unit control section for referring to the adjacent element unit connection information retaining table, on the basis of the request information received by the request information receiving section to determine an element monitoring control system capable of monitoring and controlling the adjacent element unit on the connection-accepting side, and for determining a resource for setting up the connection corresponding to the quality information in cooperation with the adjacent element monitoring control system on the basis of the result of determination by the resource candidate determining section.
Furthermore, in accordance with this invention, there is provided a computer-readable record medium retaining a network monitoring control program for monitoring and controlling, through a computer, the whole network formed by interconnection among a plurality of element units accommodating communication terminals, wherein the network monitoring control program makes the computer function as a connection setting request information receiving section for receiving connection setting request information, including identification information on one of the communication terminals requesting a connection and another one of the communication terminals accepting the connection and quality information on the connection to be set up from the connection-requesting side communication terminal, a selecting section for selecting element units constituting a path for setting up the connection on the basis of the identification information on the connection-requesting side communication terminal and connection-accepting side communication terminal included in the connection setting request information received by the connection setting request information receiving section, a request information outputting section for outputting, to an element monitoring control system for monitoring and controlling one of the element units selected by the selecting section as its object, in-element-unit connection setting request information, including identification information on the element unit adjacent to the object element unit and further including the quality information on the connection to be set up, and an quality evaluating section for receiving a connection setting control result from the element monitoring control systems receiving the in-element-unit connection setting request information from the request information outputting section, to make judgment on whether or not the connection setting control result meets the quality information included in the connection setting request information as a whole.
Still further, in accordance with this invention, there is provided a computer-readable record medium retaining an element monitoring control program for, in a network formed by interconnection among a plurality of element units accommodating communication terminals, monitoring and controlling, through a computer, at least one of the plurality of element units as its object, wherein the element monitoring control program makes the computer function as a request information receiving section for, in the case that the object element unit is selected as an element unit constituting a path for making a connection between the communication terminals, receiving, from a host system, an in-element-unit connection setting request information, including identification information on another element unit constituting the path and adjacent to the one element unit and further including quality information on the connection to be set up, a resource securing section for securing a resource needed for making the connection meeting the quality information on the basis of the request information, received by the request information receiving section, in cooperation with element monitoring control systems for monitoring and controlling the adjacent element unit, a connection setting control section for controlling the object element unit to set up the connection through the use of the resource secured by the resource securing section, and an informing section for informing the host system of the result of connection setting control by the connection setting control section.
Thus, according to this invention, the network monitoring control system monitors and controls the whole network, and selects the element units constituting the path for setting up the connection, so that the efficient utilization of the network resources becomes feasible. In addition, the element monitoring control system controls the object element unit in cooperation with the element monitoring control system for monitoring and controlling the element unit adjacent to the first-mentioned element unit this element monitoring control system controls, and therefore, it is possible to improve the parallel processing to be conducted by the element monitoring control system. Accordingly, this arrangement offers an advantage in setting up the connection meeting the Qos requirement efficiently at a high speed.